The ability to deliver an active ingredient, such as a therapeutic agent, locally to the site of need and over a prolonged period of time is important as a therapeutic method for many ailments and diseases. Many therapeutic agents are more effective if delivered at a specific site since they can be delivered in concentrated dosages at the point of interest, while maintaining an overall low dosage within the total body. Additionally, many therapeutic agents cannot be delivered by oral means because the molecules are too fragile to survive the digestive process, or because the molecules do not pass efficiently through the walls of the digestive organs. Some therapeutic agent therapies require long term dosing over the course of many months or years requiring frequent visits to a clinician for treatment. Furthermore, some therapeutic agents require delivery in places that are inconvenient for injection, such as in the eye or in internal organs. In all these cases, sustained therapeutic agent delivery through an implant or attached device would be of great benefit to patients undergoing treatment.
Accordingly, devices, systems and methods for producing desired time dosing profiles of therapeutic agents is desirable.